1. Technical Field
The present invention relates to a liquid ejecting apparatus including a plurality of liquid ejecting heads that eject a liquid, particularly to an ink jet type recording apparatus including ink jet type recording heads that discharge an ink as the liquid.
2. Related Art
There is proposed an ink jet type recording head unit as an example of a liquid ejecting head unit which includes ink jet type recording heads that eject ink droplets from nozzle openings through a change in pressure by a pressure generating unit, and a head fixing substrate (unit base) on which a plurality of ink jet type recording heads adhere to a side thereof opposite to a liquid ejecting surface in which the nozzle openings are formed (for example, see JP-A-2015-174387).
In such an ink jet type recording head unit, the plurality of ink jet type recording heads form a long nozzle array, thereby making it possible to increase a yield ratio and to decrease manufacturing costs, compared to a case where one ink jet type recording head forms a long nozzle array.
In addition, the ink jet type recording head unit includes a lifting-lowering mechanism that is capable of adjusting a position of a nozzle-formed surface with respect to an apparatus main body. As the lifting-lowering mechanism, there is proposed a mechanism configured to include an eccentric cam provided on an apparatus main body side and a driven cam that is provided on an ink jet type recording head unit side and follows the eccentric cam, in which the driven cam is caused to move in response to eccentricity of the eccentric cam, and thereby the ink jet type recording head unit is lifted and lowered with respect to the apparatus main body (for example, JP-A-2011-194819).
Since the ink jet type recording head unit holds the plurality of ink jet type recording heads, it is easy to obtain a long ink jet type recording head in an alignment direction of the heads; however, as disclosed in JP-A-2015-174387, in a case where the lifting-lowering mechanisms are disposed on both sides in the alignment direction of the ink jet type recording heads, a problem arises in that the ink jet type recording apparatus is more increased in size in the alignment direction of the ink jet type recording heads.
Otherwise, as the lifting-lowering mechanism in JP-A-2015-174387, in a case where the eccentric cam provided on the apparatus main body side comes into contact with the driven cam provided on the ink jet type recording head unit side so as to be lifted and lowered, a problem arises in that it is not possible to position a nozzle-formed surface with high accuracy due to dimensional tolerance of components, positional shifts of components, or the like.
Otherwise, in a case where it is possible to lift and lower the ink jet type recording head unit with respect to a shaft, a problem arises in that the ink jet type recording head unit tilts in a direction inclined to a lifting-lowering direction with respect to the shaft, and thereby ink droplets lands at a shifted position on an ejection target medium.
Note that such problems arise not only in the ink jet type recording apparatus, but also in a liquid ejecting apparatus that ejects a liquid other than an ink.